I've been playing around with ideas for a shallow type of speaker cabinet, a bit like the old Boston Acoustics A150, designed to sit right up against the wall.
The pic below shows the idea I have in mind, with 45 degree chamfers from the front baffle to the wall. Depth would be about 200mm (8 inches).
I'm not sure what kind of diffraction signature this will create, and whether it will mitigate the reflections off the wall.
Does anybody have a comment or opinion on this?
The pic below shows the idea I have in mind, with 45 degree chamfers from the front baffle to the wall. Depth would be about 200mm (8 inches).
I'm not sure what kind of diffraction signature this will create, and whether it will mitigate the reflections off the wall.
Does anybody have a comment or opinion on this?
An externally hosted image should be here but it was not working when we last tested it.
David Gatti said:Care to give details? What was your impression of them?
It was supposed to be an isobarik B110/T27 MTM... never finished them. The shape is a very good idea... at least i thot so 🙂
dave
Here's a more practical version.
An externally hosted image should be here but it was not working when we last tested it.
Hi Dave
our cabinet is similar to what I'm going to build .Mine will be on small stands with the bass drivers in seperate cabs .
I'm going to try a 70 degree angle .
Cheers
our cabinet is similar to what I'm going to build .Mine will be on small stands with the bass drivers in seperate cabs .
An externally hosted image should be here but it was not working when we last tested it.
I'm going to try a 70 degree angle .
Cheers
David Gatti said:Scanspeak, Audiotechnology, Audiotechnology, Dynaudio
Full-on Danish system... gonna get Jensen caps & coils? 🙂
dave
Nice to see 56oval. What's the dimensions & drivers you're using?
Why did you choose 70 degrees? A lower angle would help with diffraction.
Planet10, I don't know if I'll have any cash left, but Jenzens would be nice. Maybe just on the tweeter.
Why did you choose 70 degrees? A lower angle would help with diffraction.
Planet10, I don't know if I'll have any cash left, but Jenzens would be nice. Maybe just on the tweeter.
David,
have you considered a 300-400Hz crossing?
It would fill out the "floor dip", increase dynamics/reduce distortion and possibly give less problems with phase distortion in the 100-250Hz range which have shown to be an area of increased sensitivity to groupdelay.
/Peter
have you considered a 300-400Hz crossing?
It would fill out the "floor dip", increase dynamics/reduce distortion and possibly give less problems with phase distortion in the 100-250Hz range which have shown to be an area of increased sensitivity to groupdelay.
/Peter
David Gatti said:Nice to see 56oval. What's the dimensions & drivers you're using?
Why did you choose 70 degrees? A lower angle would help with diffraction.
Hi david
The front baffle 300mm wide,700mm high & its @ 250mm deep I think .
Drivers 1st you can't please everyone so here goes
Raven R1 ,6.5"PHL 1120 & 10"PHL3020 bass I haven't decided it might be a 15" or maybe try multi subs .
The 70 to 72 degree angle came from a totally different industry and I know someone who has tried it and it worked ,most likely 50mm roll over could work just the same and easier .
Cheers
Mal
Pan said:David,
have you considered a 300-400Hz crossing?
It would fill out the "floor dip", increase dynamics/reduce distortion and possibly give less problems with phase distortion in the 100-250Hz range which have shown to be an area of increased sensitivity to groupdelay.
/Peter
Yes Pan, at this early stage, I'm considering anywhere from 200 - 400 Hz.
I will have to do some simulations, and also figure out the optimum height for the woofer. Any suggestions on that? I'm in 2 minds, thinking fairly high for the best integration with the midrange (1st order crossover), but closer to floor for less floor bounce in the midrange.
560val, sounds like quite a nice efficient design. When do you start making sawdust?
David Gatti said:
560val, sounds like quite a nice efficient design. When do you start making sawdust?
When I stop looking at more efficient design's 😕 and cabinet materials .
Cheers
My next (re)build will be similar too - simply because I don't have the facilities to build Troels' PMS...
My last two builds used the same drivers, one in 300mm pipes, the other in wide but thin cabs, 500x170 - it was much easier to get BSC & driver balance right in the wide cabs (& they suit available space better)
I'm rebuilding my all Peerless system, (drivers from before the move to China) 3 way, this will be bi-amped, current xover 200Hz 1st order passive, but on Pan's suggestion I'll try higher.
I want to get the Baffle width & xover freq 'co-ordinated' so that I can tweak BSC simply by changing the level on the woofer amp
re 'optimum height for the woofer' - I don't like woofers too close to the floor, I seems to muddy up the sound a bit to me.
My last two builds used the same drivers, one in 300mm pipes, the other in wide but thin cabs, 500x170 - it was much easier to get BSC & driver balance right in the wide cabs (& they suit available space better)
I'm rebuilding my all Peerless system, (drivers from before the move to China) 3 way, this will be bi-amped, current xover 200Hz 1st order passive, but on Pan's suggestion I'll try higher.
I want to get the Baffle width & xover freq 'co-ordinated' so that I can tweak BSC simply by changing the level on the woofer amp
re 'optimum height for the woofer' - I don't like woofers too close to the floor, I seems to muddy up the sound a bit to me.
PeteMcK said:My next (re)build will be similar too - simply because I don't have the facilities to build Troels' PMS...
My last two builds used the same drivers, one in 300mm pipes, the other in wide but thin cabs, 500x170 - it was much easier to get BSC & driver balance right in the wide cabs (& they suit available space better)
I'm rebuilding my all Peerless system, (drivers from before the move to China) 3 way, this will be bi-amped, current xover 200Hz 1st order passive, but on Pan's suggestion I'll try higher.
I want to get the Baffle width & xover freq 'co-ordinated' so that I can tweak BSC simply by changing the level on the woofer amp
re 'optimum height for the woofer' - I don't like woofers too close to the floor, I seems to muddy up the sound a bit to me.
Bi-amping would be nice, and I leave that as an optional upgrade further down the track.
I agree about the bass driver close to the floor tending to muddy the sound, and I suspect that's more about crossover interaction rather than floor bounce. Since the 12" woofer already has a 6cm or so depth, then you add the increased path length to the listener's ear, it's tough to compensate for it in the crossover.
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